import pandas as pd
from datetime import datetime, timedelta

def determine_season(input_date_str):
    df = pd.read_csv('weather.csv')
    
    df['Date'] = pd.to_datetime(df['Date'])
    
    temperatures = df['Temperature(Celsius)(avg)'].values
    
    sliding_avg = []
    for i in range(len(temperatures)):
        if i < 4:
            sliding_avg.append(None)  # 前4天无法计算5天滑动平均
        else:
            avg = sum(temperatures[i-4:i+1]) / 5
            sliding_avg.append(avg)
    
    seasons = {
        'spring_start': None,
        'summer_start': None,
        'autumn_start': None,
        'winter_start': None
    }
    
    for i in range(4, len(sliding_avg)):
        if sliding_avg[i] is not None and sliding_avg[i] >= 10 and sliding_avg[i] < 22:
            seasons['spring_start'] = df['Date'].iloc[i-4]  # 滑动窗口的第一天
            break
    
    for i in range(4, len(sliding_avg)):
        if sliding_avg[i] is not None and sliding_avg[i] >= 22:
            seasons['summer_start'] = df['Date'].iloc[i-4]
            break
    
    if seasons['summer_start'] is not None:
        summer_idx = df[df['Date'] == seasons['summer_start']].index[0]
        for i in range(summer_idx + 5, len(sliding_avg)):
            if sliding_avg[i] is not None and sliding_avg[i] < 22 and sliding_avg[i] >= 10:
                seasons['autumn_start'] = df['Date'].iloc[i-4]
                break
    
    # 第一次滑动平均 < 10℃ 为入冬
    for i in range(4, len(sliding_avg)):
        if sliding_avg[i] is not None and sliding_avg[i] < 10:
            seasons['winter_start'] = df['Date'].iloc[i-4]
            break
    
    input_date = datetime.strptime(input_date_str, '%Y-%m-%d')
    
    # 判断输入日期的季节
    if seasons['spring_start'] is not None and input_date >= seasons['spring_start']:
        if seasons['summer_start'] is not None and input_date >= seasons['summer_start']:
            if seasons['autumn_start'] is not None and input_date >= seasons['autumn_start']:
                if seasons['winter_start'] is not None and input_date >= seasons['winter_start']:
                    return '冬季'
                else:
                    return '秋季'
            else:
                return '夏季'
        else:
            return '春季'
    else:
        return '冬季'

if __name__ == "__main__":
    input_date = input().strip()
    print(determine_season(input_date))